I don't at all see how the fraction relates to the difference equation, either. You may need to explain what is going on, and what you are doing, a bit more.
–
Ben MillwoodJun 26 '12 at 12:34

Sorry my mathematical language is not good, I was not sure if this an equation or fraction. This is z transform of a signal and I want to calculate first 5 samples if $x_0=1$ and $x_1$ to $x_4$ are $0$
–
Sean87Jun 26 '12 at 14:51